Design of Voltage Acquisition Module with Adjustable Parameters FIR Filter.

In order to reduce the high frequency noise in voltage acquisition signal effectively, the voltage acquisition module with adjustable finite impulse response (FIR) filter parameters was designed. FIR digital filter was applied in this acquisition module to filter out the high frequency noise in the acquisition signal based on the advanced RISC machine (ARM) and field programmable gate array (FPGA) hardware platform. The filter coefficients were calculated and generated by ARM automatically according to the filter parameters such as sampling frequency and cut-off frequency. The improved structure of direct filter was adopted by FPGA. The filter structure was adjusted according to filter parameters. The calculation of filter coefficient and acquired data was completed. The parameter adjustable FIR filter was realized by ARM and FPGA work together. The experimental results show that the voltage acquisition module has high voltage acquisition accuracy and its maximum acquisition relative error absolute value is 0. 22%. The module can automatically complete the calculation of FIR filter coefficient and adjust the filter structure according to the set filter parameters. The high-frequency noise in the signal is filtered out effectively at the same time of signal acquisition. [ABSTRACT FROM AUTHOR]